Home
Class 11
PHYSICS
Two forces P and Q of magnitude 2F and 3...

Two forces P and Q of magnitude 2F and 3F, respectively, are at an angle `theta` with each other. If the force Q is doubled, then their resultant also gets doubled. Then, the angle `theta` is

A

`30^(@)`

B

`60^(@)`

C

`90^(@)`

D

`120^(@)`

Text Solution

Verified by Experts

The correct Answer is:
D
`R^(2) = 4F^(2) + 9F^(2) + 2 xx 2F xx 3F cos theta`
`rArr 4 =(4 + 36 + 24 cos theta)/(4 + 9 + 12 cos theta)`
`rArr 13 xx 4 + 12 xx 4 cos theta = 40 + 24 cos theta`
`rArr cos theta = (40-52)/(48-24) = (-12)/24 =-1/2`
`rArr theta = 120^(@)`
Promotional Banner

Similar Questions

Explore conceptually related problems

One of the following forces is double and the other resultant is equal to the greater force. The angle between them is

The resultant of two forces 3P and 2P is R. If the first force is doubled then resultant is also doubled.The angle between the two forces is

The resultant of two foces 3P and 2P is R. if the first is doubled the resultant is also doubled. Then , angle between two forces.

Two forces of equal magnitude act at a point making an angle theta with each other. If the direction of one of the forces is reversed, the direction of the resultant will turn through

Two forces, each of magnitude F have a resultant of the same magnitude F. The angle between the two forces is

Two forces each of magnitude 2N, act at an angle of 60^(@) . What is the magnitude of the resultant force ?

Two forces of magnitudes 3N and 4 N act together on an object making an angle 60^(@) with each other. Find the resultant force acting on the object.

Two forces of magnitudes P and Q are inclined at an angle (theta) . The magnitude of their resultant is 3Q. When the inclination is changed to (180^(@)-theta) , the magnitude of the resultant force becomes Q. Find the ratio of the forces.